1. Field of the Invention
The present invention relates to piping systems and, more particularly, pertains to a new fluid diverter system adapted to improve drainage therethrough.
2. Description of the Prior Art
Over the years, various piping systems have been developed to divert or distribute the flow of a wide variety of fluids under various operating conditions. Also known are diaphragm valves, such as the typical diaphragm valve 100 shown in FIGS. 6A and 6B, wherein the valve body 101 has a curved inlet port 102, rising up to a "weir" 104 on which a rubber diaphragm 106 seats and unseats to act as a closing element. The actuation of the diaphragm 106 is normally accomplished by a screw mechanism 108 in a bonnet 110. The valve body 101 defines an outlet port 112. FIG. 6A shows the plunger of the screw mechanism 108 in a lowered position such that the diaphragm 106 sits on the weir 104 thereby closing the valve 100, whereas FIG. 6B illustrates the plunger in a raised position, whereby the valve is open as there is defined a passage between the diaphragm 106 and the weir 104 which allows for fluid communication between the inlet port 102 and the outlet port 112.
In known fluid diverter systems, the flowing medium may be, for instance, diverted by the use of two valves connected to each other by means of a tee branch fitting defining an inlet passage in flow communication with two outlet passages or, alternatively, by the use of a multiported valve, such as a three-way valve. Basically, both systems operate by closing a closure member to block fluid flow through one outlet passage, thereby directing the incoming flow to the other outlet passage. One problem associated with these systems is that some of the fluid remains trapped within the closed outlet passage, upstream of the closure member, thereby giving rise to bacteriological growth and crystallisation of chemical processed media. Obviously, this situation is not acceptable in pharmaceutical, biotech and photo emulsion applications where cleanliness and sterility are essential.
In FIG. 7, two diaphragm valves 100 are used to divert the fluid flowing in an inlet pipe 114 to either one of the inlet ports 102 of the diaphragm valves 100. In FIG. 7, the upper valve 100 is closed while the lower valve 100 is open. This arrangement causes dead lag or stagnation of fluid at the inlet side of the closed valve, as indicated by the grey area indentified by reference numeral 116 in FIG. 7.
Accordingly, attempts have been made to reduce the amount of stagnant fluid in such diverter piping systems. For instance, U.S. Pat. No. 5,273,075 issued on Dec. 23, 1993 to Skaer and U.S. Pat. No. 5,427,150 issued on Jun. 27, 1995 to Skaer et al. both disclose a multiported diaphragm valve. Such multiported diaphragm valves are schematically represented in FIG. 8, wherein a multiported diaphragm valve 120 comprises a valve body 122 defining an inlet port 124 and two outlet ports 126. The inlet port 124 opens onto a chamber 128 which is in flow communication with both outlet ports 126. A pair of diaphragms 130 are provided for directing the fluid flow emerging from the chamber 128 through one of the two outlet ports 126. This arrangement still leaves a stagnant area upstream of the closed diaphragm, as shown at reference numeral 132 in FIG. 8.
Although the multiported diaphragm valves described in the above mentioned Patents decrease the amount of fluid which remains stagnant in the portion of the closed fluid passage located immediately upstream of the diaphragm associated therewith, it has been found that there is a need for a new multiported valve which is adapted to virtually eliminate the presence of stagnant fluids within the valve.